Heating apparatus



Feb. 20, 1940.

A. c. GRANTl HEATING APPARATUS Filed Jan. 1a, 1954 ARTHUR C. GRANT Patented Feb. 20, 1940 HEATING APPARATUS Arthur C. Grant, St. Paul, Minn., assignor to Minneapolis-Honeywell Regulator Company, 1 Minneapolis, Minn., a corporation of Delaware Application. January 18, 1934, Serial No. 707,080

8 Claims.` (Cl. :J8-A33) The present invention relates to the art of distributing fluids and the problems to be solved by this invention and the manner in which they are solved will be discussed in connection with a at the desired vtemperatifie,'the other `compartments may bemaintained attemperatures which are either higher or lowerthan contemplated` and desired., A'

In order; to'obviatev this difficulty, `in'some instances, the various ducts have been provided with returns or by-passes whereby, when a compartment is closed off, the ow of air while being prevented from reaching the compartment is vention, is the provision of` a fluid distribution,V

warm air heating system but it is to be expressly allowed to flow through the duct in order that understood that the invention has utility in systhe proper distribution will be maintained. Obtems of fluid distribution other than warm air viously, such a remedy is expensive because of heating systems, the additional duct work since this by-pass air In a warm air heating system, it is usual to should be returned to the Warm air furnace and provide a Warm air furnace or other means for if it is not returned, it necessarily follows that a l0 heating the air, together with pipes or ducts for large amount of heat is being wasted. The 'presleading the heated air to the various compartent invention therefore contemplates a simple ments to be heated. It is well recognized that arrangement Wherebythe desired distribution of various compartments require varying volumes of air to the various compartments heated by a heated air per unit of time by reason of differwarm air furnace is maintained when the flow of ences in size, differences in heat loss and, in` air. through one or more of the ducts leading to some instances, because it is desired to maintain the compartments is completely shut oil. varying temperatures in various compartments. One of the objects of the present invention is In order to obviate the necessity of separate the provision of a system of distributing fluid to controlling means for controlling the flow of air a plurality of points of use having different re- `to each of the compartments, it has beenusual quirements in which the distribution system is to provide a single control responsive to the tern-y arranged to give the proper distribution of Huid perature of only one of the compartments Whereto all of the points of use when all of them are in by the temperature of that compartment is operation, together with means for automatically maintained at the desired point and to maintain maintaining `the proper distribution to the rethe desired temperatures in the other compartmaining points 'of use when one or more of the ments by arranging'the ducts or pipes in such points of use is rendered inoperative. manner that the `proper amount of heated air A further object oi the invention is the prois distributed to each of these compartments. vision of an air distribution system wherein air IThis is generally accomplished by providing ducts is adapted tov be distributed through properly of different sizes and in some instances additional arranged ducts or pipes so that different desired means such as individual dampers are also proows or volumes of air are delivered to the de vided `in orderV that the proportional amount 'of sired points, together with Ameans for automatilthetotal air delivered to each compartment in, cally` maintaining the same flow throughthose response to the control in the controlling com` ducts still in operation when some of the ducts 35 partment may be properlyadjusted. are closed off` so as to prevent theY flow of air Such systems are satisfactory when all'of the therethrough. y r ducts are open so that theproper balance in the Another object of the invention is the provision iiow of air to all `of the compartments can be of a warm air heating system of the type whereinv -`rriaintained by reason` of the aforementioned la plurality of, `ducts leadingtoa plurality of 40 proper design ofthe ducts. However, it is often compartments `to be heated are proportioned or desired to block off the flow of'ai'rlto one or `more yarranged to give the desired flow `or volume or of the compartments.. When `this is done, apf proportion of air to each and every one ofthe proximately the same total` volume of air is then `compartments When`1all=of the ducts are, open to available-for a lesser number of vconlpartrnents the passage of air` and means for maintaining l and inasmuch as the ductshavetbeen arranged to` this proper proportion or flow orvolume to those givezthe proper 4flow of air to each` compartment ducts still in operation when one or more of them only whenall of the ducts are open, the distribufis placed out of operation and the` `flow ofuair tion orbalance is-upset. This, means that While `therethrough obstructed. the main controlling.compartmentis maintained More specifically, an object of the `present insystem by which varying volumes ofjliuid are f of usevhaving differentl volume requirements, and providing automatic means for maintaining the delivered per ,unit of time to a plurality of points Adamper II and usual check damper I2.

delivery pressure constant whereby when delivery of fluid to one of said points is obstructed, the volume delivered to the remaining points per unit of time remains constant. In the embodiment to be hereinafter described, a blower or fan serves to pass air through'a warm air furnace and then through a plurality ofl properly proportioned ducts to a corresponding number of rooms or compartments and a device responsive to the delivery air pressure operates a damper to limit the total quantity of air moved by the fan or blower per unit of time` whereby the air delivery pressure and the flow of air through each duct that is in operation remains constant.

Further objects of the invention will be found in the detailed description, the appended claims and the drawing.

For a more complete understanding of the invention, reference may be had to the following detailed description and the accompanying single drawing which is a diagrammatic showing of one application of the instant invention.

Referring to this single drawing, the invention is shown as applied to a warm air heating system which includes a warm air furnace generally indicated at I0. The heat output `of the furnace is shown as being controlled by the ordinary draft Air is supplied to the furnace I0 ,byl means of a return pipe I3 which communicatesv with a blower I4, preferably electrically operated.v The blower discharges this air into the furnace III through'a pipe or duct I5. The air then flows through the furnace and into the usual warm air heating chamber I6 thereof, where the air is heated, from hence it is lead by suitable ducts or pipes 'to the rooms or compartments tobe-heated. In the instant embodiment of the invention, four rooms 40. II, I8, I9 and 20 are illustrated. The room I1 requires more heat per unit of time than any of, the other rooms, perhaps because of its exposure or size or the temperature which it is desired to maintain thereinr so a large duct 2| i connects with the air heating chamber I6 and a register 22 located in the room I1. 'I'he room ISas shown requires a smaller amount of heat per unitof time as indicated by the fact that the duct 23 register 24 of room I9 is slightly smallerthanthe duct 2|. In a similar manner, two progressively smaller ducts 2` and 26 lead from air heating chamber I6.to registers 21 and 28 located respec tively in rooms I8 and 20. Each of theregisters is provided with the usual shutter 29 whereby any one of the ducts 2|, 25, 23 or 26 may be shut off so as to interrupt the flow of air therethrough and to the corresponding room |1I8, YII'Ilor 20.

With the arrangement thus far described, the ducts 2|, 25, 23 and 26 have beenv proportioned in such manner that when all of them are open to the flow of air, the proper proportional part of the total air delivered by the blower I4. and heated by the furnace III will be delivered to each of the rooms. With no additional mechanism, if the register 22 leading to room I1 were shut off, the total amount of air delivered by blower I4 would thereupon be distributed to the three remaining rooms I8, I 9 and 20. This would result in an increase in the velocity of the air flowing through the respective ducts 23, 25 andv 26. Such .an increase in velocity is undesirable for several reasons. For one thing, the velocity of air iiowing into the room has a bearing pon the quickness of response upon the main controlling thermostat located in some one of the rooms with the result that changes in velocity of the air delivered to the rooms results in changes in 'the response of the heating system. Furthermore, an increased velocity may set up an in-' the remaining rooms I8, I 9 and 20 will change from that desired and contemplated in originally laying out the heating system so that the desired `temperatures will not be maintained `in those rooms which do not contain the control device.

To overcome these detrimental effects, the present invention provides a pressureresponsive device herein shown as a diaphragm mechanism of well-known construction and operation, indi--` cated at 30. This diaphragm mechanism responds to the pressure on the outlet side of blower I4 and therefore responds to the pressure in the furnace or ris a measure of the air delivery pres--Y sure. The return I3 is provided witha damper 3| and suitable linkage 32 interconnects the damper 3| and the diaphragm mechanism 30. Now as the pressure of the delivered air within the furnace or duct I5 rises, due to closing oif of one of the delivery ducts, the diaphragm in the diaphragm mechanism 30 will lift and move the damper v3| towards .closed position so as to reduce the` amount of air delivered lby the blower I4 per 'unit of time. In this manner, a, constant air delivery pressure is maintained and, as a result; the ow of air through each of the ducts 2|,v 25, 23,-and 26 will always remain constant.

With the parts in the position shown in the drawing, all of the ducts, 2|, .25, 23 and 26 are open and the blower I4 is delivering a maximum quan` ,tity of air and just maintaining the pressure at Athe desired point as indicated by damper 3| being in wide-open position. Now-if the register 22 should be closed so asto stop the f1ow of air through duct 2| and to room I1, rthe total flow of `air in attempting to passthrough ducts 25, 23

and 21 must vnecessarily increase in velocity with the result that the airdelivery .pressure or the .f

, air pressure induct I gwill increase. Thediaphragm in diaphragm mechanism 30w'lll there- 'l fore be raised and the' damper 3| partially closed. 'I'he vtotal air'delivered by'blower I4 will-there upon decrease and the velocity of the air passing through pipe 25, 23 and 26 will return to normal as will the' pressure in duct? I5. In 4this manner, by maintaining a constant pressure in passage I5 or a constant air delivery pressure, by limiting the air delivered byv blower I4; there will always be a constant flow or velocity of air through whichever of theductsf2I, 25, 23 and 26 may happen to be open so that the amount of air de- I livered to each room Vper unit of time always remains constant when its respective'duct is open. It therefore follows that the proportion of air delivered to each of therooms will likewise remainvconstant. It is contemplated that the draft damper I I and check damper I2, as well as the blower I4, will be controlled by 'a thermostat located in some one of the compartments I1, I 8, I9 or 20 in any of the well-known manners of control such as that disclosed in Edward F.

Edgecombe, Jr., Patent Re. 15,531 which issued January 23rd, 1923.

While the invention has been explained in connection with the distribution of air in a warm air heating system, it will be apparent that it is likewise applicable to the delivery of air from air conditioners and other air treating devices and for that matter to the distribution of air or any other fluid wherein it is desired to distribute varying quantities of fluid to a plurality of points per unit of time and when under some conditions, it is desirable to render a portion of the distribution system inoperative.A Furthermore, many changes can be made by those skilled in the art Without departing from the spirit of the invention and I therefore intend to be limited only by the scope of the appended claims.

I claim:

1. A distribution system for circulating fluid, comprising, in combination, a chamber, means for conveying the fluid from said chamber to a plurality of points of use of diiferent requirements in volume per unit of time, `means located on the upstream side of said points of use for circulating the fluid from said chamber through said conveying means and to said points of use, means for at least partially blocking off the flow of fluid to one` of said points of use and through corresponding parts of said conveying means, and means to automatically maintain a constant uid pressure on said conveying means including a device constantly responsive to the pressure produced by said circulating means on its downstream side but ahead of said points of use.

2. In an air conditioning system, in combination, an air conditioning chamber, duct means connecting said air conditioning chamberto a plurality of spaces to be conditioned and requiring different amounts of conditioned air per unit of time, an inlet duct for said air conditioning chamber, circulating means located on the upstream side of said spaces and arranged to pass air through said inlet duct, air conditioning chamber and duct means to said spaces, means to restrict the effective area of at least a portion of said duct means, damper means located in said inlet duct, and a device responsive to the pressure on the downstream side of said circulating means but ahead of said spaces in control of said damper means to maintain said pressure constant.

3. A system of the class described, comprising, in combination,a warm air furnace, a plurality of enclosed spaces requiring different volumes of air per unit of time heated thereby, a plurality of ducts associated with said spaces and furnace and arranged to furnish the proper amount of air to each of said spaces when all of said spaces are receiving air, means located on the upstream side of said ducts for inducing a flow of air from said furnace and through said ducts to said spaces, means for closing off at least a portion of one of said ducts, and means to automatically maintain a constant pressure on said ducts including a device responsive to the pressure between said air flow inducing means and said ducts.

4. In combination, a warm air furnace, an inlet duct for the furnace, duct means connecting the furnace to a plurality of compartments to be heated and requiring different proportions of the lconstant at all times.

5. In an air conditioning system for conditioning the air in a plurality of spaces, the" combination of, an air conditioning chamber having means for conditioning air which is circulated therethrough, duct means for conveying conditioned air from the air conditioning chamber to the plurality of spaces to be conditioned, fan l means for circulating conditioned air from the air conditioning chamber through the duct means to the spaces to be conditioned, dam-pers associated with said duct means for regulating the amount of conditioned air delivered to each space for maintaining desired air conditions in each space, and means including means responsive to the static pressure on the discharge side of the fan means for regulating the amount of air circulated by the fan means to maintain the static pressure in the duct means substantially constant whereby the velocity of the conditioned air delivered to each space remains substantially constant regardless of the amount of air delivered to each space.

6. In an air conditioning system for conditioning the air in a plurality of spaces, the combination of, an air conditioning chamber having means for conditioning air which is circulated therethrough, duct means for conveying conditioned air from the air conditioning chamber to the plurality of spaces to be conditioned, fan means for circulating conditioned air from the air conditioning chamber through the duct means to the spaces to be conditioned, dampers associated with said duct means for regulating the amount of conditioned air delivered to each space for maintaining desired air conditions in each space, damper means located on the inlet side of the fan means for regulating the amount of air circulated by the fan means, and means responsive to the static pressure on the discharge side of the fan means for positioning said damper means to maintain the static pressure of the air in" said duct means substantially constant whereby the velocity of the air delivered to each space remains substantially constant regardless of the amount of air delivered to each space.

7. In an air conditioning system forconditioning the air in a plurality of spaces, the combination of, an air conditioning chamber having means for conditioning air Which is circulated therethrough, duct means for conveying conditioned air from the air conditioning chamber to the plurality of spaces to be conditioned, an inlet duct for conveying air to the air conditioning chamber, fan means located between the inlet duct and the air conditioning chamber for circulating air from the inlet duct through the air conditioning chamber and duct means to the spaces to be conditioned, dampers associated With said duct means for regulating the amount of conditioned air delivered to each space for maintaining desired air conditions in each space, and means including means responsive to the static pressure on the discharge side of the fan means for regulating the amount of air circulated by the fan means to maintain the static pressure in the duct means substantially constant Whereby the `velocity of the conditioned air delivered to each space remains substantially constant regardless of the amount of air delivered to each space.

8. In an air conditioning system for conditioning the air in a plurality of spaces, the combination of, an air conditioning chamber having means forconditioning air which is circulated therethrough, duct means for conveying conditioned air from the air conditioning chamber to the plurality of spaces to be conditioned, an inlet duct for conveying air to the airconditioning chamber, fan means located between the inlet duct and the air conditioning chamber for circulating air from the inlet duct through the air conditioning chamber and duct means to the spaces to be conditioned, dampers associated with 4mains substantially constant regardless of the amount of air delivered to each space.

ARTHUR c. GRANT. 

